Magnetic curvature: Difference between revisions

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The tangent plane to any flux surface is spanned up by two tangent vectors: one is the normalized magnetic field vector (discussed above), and the other is
The tangent plane to any flux surface is spanned up by two tangent vectors: one is the normalized magnetic field vector (discussed above), and the other is


:<math>\vec b_\perp = \frac{\vec \nabla \psi \times \vec B }{|\vec \nabla \psi \times \vec B|}</math>
:<math>\vec b_\perp = \frac{\vec \nabla \psi}{|\vec \nabla \psi|} \times \frac{\vec B}{|\vec B|}</math>


The corresponding perpendicular curvature is
The corresponding perpendicular curvature (the curvature of the flux surface in the direction perpendicular to the magnetic field) is


:<math>\vec \kappa_\perp = \vec b_\perp \cdot \vec \nabla \vec b_\perp</math>
:<math>\vec \kappa_\perp = \vec b_\perp \cdot \vec \nabla \vec b_\perp</math>